fog lights

Not legally. The car would have to be rewired. In most juristictions, the headlamps must be on when the fog lamps are on.

 

Forgive me if this is a stupid question, but I've seen several people write that you can't have the fog lights on without the main headlights being on. Can't you just turn the headlight control to the first setting, running lights only, and then turn on the fog lights? I thought I had done this before, and it would make a little bit of sense, but maybe I just imagine that I had done it because it would be stupid to use fog lights and headlights at the same time.

 

<div class='quotetop'>QUOTE(Ichabod @ Aug 20 2006, 12:26 PM) [snapback]306258[/snapback]</div>

No, the foglights only come on with the headlights on.

They don't seem to put out much light (hard to tell since the headlights are on too) so I'm not sure what use they'd be on their own.

 

<div class='quotetop'>QUOTE(Godfrey DiGiorgi @ Aug 20 2006, 10:08 AM) [snapback]306272[/snapback]</div>

The stock fog lights are aimed a little too low to be used alone. The reason for this is that they're designed to be used with the headlights on (to add corner light) but since the beam pattern is circular (a good fog lamp is oval) they kept the aim low to cut down on the stray light in front of your eyes (illuminating the fog).

I don't recall anyone finding a good way to re-aim them either.

People complain about them a lot, but they do do what Toyota intended. If you want good fogs, go aftermarket.

 

I am going to sound old again! Fog lights are supposed to be amber (as they were in the old days) so that they don't glare back at you and you should be able to use them without headlights. In my '93 Pontiac and in most GM cars you can turn on the foglamps when the light switch is in the parking light position, which also illuminates the marker and tail lamps. Of course on GM cars the DRLs are on also.

I have not really seen real foglamps in years. What they have been putting on cars for the last 15 years are really accent lamps. They must be because of the number of cars I see on beautiful, clear nights and calm, sunny days running with headlamps and fog lamps. They must be going after the look; they are certainly not using the function!

 

<div class='quotetop'>QUOTE(marjam @ Aug 20 2006, 10:59 AM) [snapback]306297[/snapback]</div>

The companies that make real fog lamps put a considerable amount of research into the light colors and beam patterns. As for amber fog lamps working better, it's not the amber or yellow, it's the absense of violet/blue (basically, the shortest wavelengths of visible light) that counts. The reason for this is the way your eyes work, not because yellow light penetrates fog better (which is a myth. For that to occur, the water droplet size would have to be smaller than the wavelength of the light - it isn't). If you'd like to read more google Rayleigh Scattering.

OK, back to the eye... the cones in your eyes are good at seeing light down to about a 400nm wavelength (blue), but shorter wavelengths are harder for our eyes to define (violet) and are preceived more as glare than color as the wavelength gets shorter (and eventually becomes invisible - ultraviolet). So a good fog lamp needs some of the low wavelength light removed. In the old days they'd just coat the bulb or reflector, or housing with yellow to filter out the blue light. The problem with this approach was that it would reduce the total amount of light, so it was kind of like one step forward, one step back. Modern fog lamps (good ones, that is) use a dichroic filter (either in the bulb glass itself, or in the housing) to selectively filter out low wavelength light. When using this approach, the light can still appear white to your eye, but is just as effective in fog as the old yellow/amber lights were, and is brighter for the same amount of electricity (so lower heat). Industry folks call these type of lights "selective yellow" or "selective white".

As for having the main headlights on... contrary to what many people think, real fog lamps are designed to augment your headlights and are meant to be used in conjunction with them. A good fog has a wide beam (say, 90 degrees) and is flat i.e. oval beam pattern with a good cut-off, adding illumination to the road surface and edges without throwing much light up into the fog in front of the driver's face. And that's what's wrong with most factory fogs. The beam pattern is usually too round.

<div class='quotetop'>QUOTE(marjam @ Aug 20 2006, 10:59 AM) [snapback]306297[/snapback]</div>

Yep, poseurs.

 

Thank you, Wilco.

I learn so much on this BB.

<div class='quotetop'>QUOTE(Tideland Prius @ Aug 21 2006, 02:54 AM) [snapback]306596[/snapback]</div>

I want to do that but have found no one in the Washington DC area to help me. I am not very mechanical and don't want to mess things up.

 

<div class='quotetop'>QUOTE(Tideland Prius @ Aug 21 2006, 01:54 AM) [snapback]306596[/snapback]</div>

Check your local laws, too - there's a reason they're called "parking lights". In many states (Colorado and Kansas for sure, and I know Texas was this way back in the early 80s) if the light levels are low enough to require lights at all (visibility degraded to less than 1000 feet, to be exact (or between 1/2 hour after sunset and 1/2 hour before sunrise)) you are required to have your headlights on - driving with your parking lights on is illegal. This also keeps you from being one of those idiots who drives with just his parking lights on after dark.

 

You're not missing anything. My Prius has them and they are purely asthetic/decoration

 

<div class='quotetop'>QUOTE(Tideland Prius @ Aug 21 2006, 07:15 PM) [snapback]307149[/snapback]</div>

I've always been bugged by North American and Asian autos not using the rear foglights that are found in most EU countries.

A co-worker has a 2006 Range Rover HSE and it has rear fog lights. Driving in heavy snow/rain/fog that might be all the difference between avoiding a collision and getting rear ended.

I'm sure it has something to do with the average North American driver having the IQ of canned Spam with the attention span of a purely theoretical particle. They might get "confused" by those high intensity red lights

 

<div class='quotetop'>QUOTE(jayman @ Aug 21 2006, 05:29 PM) [snapback]307161[/snapback]</div>

LOL! :lol:

 

<div class='quotetop'>QUOTE(jayman @ Aug 21 2006, 07:29 PM) [snapback]307161[/snapback]</div>

What the heck does that mean? I think I'm offen - oooh! pretty butterflies!!!